Electronic devices emit electro-magnetic energy in radio frequency (RF) range. These emissions can interfere with the functioning and performance of other nearby electronic devices that may be operating in the similar RF range. Some electronic devices with moderate or high-power wireless transmitters can produce electromagnetic fields strong enough to interfere with the operation of other electronic devices within certain range.
To prevent electromagnetic interference from one device to affect the functioning of other devices, Federal Communication Commission (FCC) defines guidelines and regulation for device manufacturers to limit electromagnetic interference from their products within certain defined electromagnetic interference limits. Electronic products for residential use such as for example, handheld devices, computers, televisions, game machines, and other electronic home products are covered under Part B of FCC electromagnetic interference regulation. Manufacturers of electronic devices for residential use must comply with Part B of FCC electromagnetic interference regulations. Even when an electronic device complies with the electromagnetic interference regulation, in cases where multiple electronic devices function together, the aggregate electromagnetic interference may still exceed regulated limits. For example, when multiple handled device such as mobile phones, calculators, electronic game machines, and pagers are placed in a single charging bay for charging or data transfer, then the aggregated electromagnetic interference of all devices in the charging bay may exceed regulated legal electromagnetic interference limit, resulting in the violation of Part B electromagnetic interference regulation.
Typical solutions to minimize electromagnetic interference use an increased number of layers on the PCB and add additional electronic components or shielding. These solutions add product cost and complicate manufacturing process.